Suppressor design has, for over 100 years, included the basic structure of a series of baffles and chambers which trap expanding gasses as they exit a muzzle. Though there have been many variations on this core design concept, virtually every design has followed this basic design. However, this basic design is flawed because it traps the pressure in the initial chamber and significant pressure is generated on the first baffle, commonly called the “blast baffle”. This pressure and heat buildup in that first chamber creates several negative effects that include back pressure into the barrel. This back pressure often causes the firearm to malfunction from added carbon and fouling from the gasses. Additionally, over gassing the system and increasing the cyclic rate creates additional stresses on the components that lead to mechanical failures. Another negative effect of excessive backpressure is that gasses and debris are blown back into the operator's face.
The other shortcomings of the basic design is that the gasses must exit out of the small holes either back into the barrel, or forward against the base of the bullet, which can cause turbulence and accuracy issues.
Also, most basic designs do not create optimum gas expansion, diffusion and cooling, because the designs provide poor heat transfer “heat sink” capabilities. Accordingly, gas expansion is limited and gas pressures are maintained until the bullet exits the suppressor, at which point the hot gasses finally are allowed to exit the small bore hole at relatively high pressure, velocity and heat. Pressure, velocity, and heat are the main contributors to the sound signature.
One other area that adds to the overall sound signature of these designs is that the bullets may push a supersonic cone of air ahead of the bullet and as the bullet passes through each chamber a sonic boom is created in the ambient air within each chamber and again as the bullets exit the suppressors. Another design failure of the basic design is that the ambient air contained in the chambers is ignited and results in a large flash out the end of the suppressor. Because this flash may attract the attention of an armed enemy and notify the enemy of the operator's location, this flash is known to members of the armed forces as the “bloom of death”.